1. Field of the Invention
This invention relates in general to the field of handling an integrated circuit (xe2x80x9cICxe2x80x9d) device, and more particularly to an improved apparatus and method of inverting an IC device.
2. Description of the Related Art
Various schemes have been proposed for moving IC devices between carriers or trays and the test head of a test system. A common approach is to use a vacuum chuck to pick up a device from a tray and to place it in a contactor on a load board which provides the interface to the test head of the test system. This is known as xe2x80x9cpick and placexe2x80x9d and examples of this are found in U.S. Pat. No. 5,469,953 and U.S. Pat. No. 5,290,134 which describe the use of a suction chuck to lift an IC device from a tray and lower it into a tester or into another tray. U.S. Pat. No. 5,330,043 describes a pair of transfer heads mounted at forty-five degrees to a rotatable drive shaft and ninety degrees to each other. Each transfer head has a vacuum chuck for picking devices from a horizontal tray and a drive arm for lifting the head and advancing it to a vertical test head after rotation of the shaft. Devices are returned to the tray by reverse rotation and lowering of the transfer head. One head is over the tray when the other is against the test head. Other pick and place systems have one or more vacuum chucks on a mechanism for X, Y, and Z motion to allow devices to be placed in testers.
All of these pick and place methods place the IC device in the same orientation in which they pick it up. The IC device is typically taken from a tray, on which the IC device is resting in a xe2x80x9clive bugxe2x80x9d position (connections down), by the pick and place handling system. The vacuum handling device of the pick and place system picks up the IC device from its tray and places the IC device on a carrier, still in a live bug position. The carrier slides or moves through the conveyor towards the test site. At times, however, it is useful to transpose the IC device from its xe2x80x9clive bugxe2x80x9d position to a xe2x80x9cdead bugxe2x80x9d position, that is, a position where the connectors of the IC device are pointing up instead of down.
Therefore, a need has arisen for an improved apparatus and method of inverting an IC device.
A device and method are described for gripping a semiconductor device, rotating the device through an arc of approximately one-hundred eighty degrees, and releasing the semiconductor device. The semiconductor device is rotated in a vertical plane, thereby inverting it.
Briefly, in accordance with one aspect of the present invention, there is provided an inversion handler for inverting a device under test (xe2x80x9cDUTxe2x80x9d). The inversion handler includes a holding assembly and a shaft. The holding assembly is for releasably securing the DUT. The shaft is coupled to the holding assembly and is adapted to be rotated, thereby rotating and eventually inverting the holding assembly.
Briefly, in accordance with another aspect of the present invention, there is provided a method of inverting a device under test (xe2x80x9cDUTxe2x80x9d). The method includes releasably securing the DUT with a holding assembly such that a point of contact is made between the DUT and the holding assembly. The holding assembly is coupled to a shaft. The method further includes rotating, and eventually inverting, the releasably secured DUT by rotating the holding assembly while maintaining the point of contact between the DUT and the holding assembly. The method further includes releasing the releasably secured DUT.
Briefly, in accordance with another aspect of the present invention, there is provided an inversion handler for inverting an integrated circuit (xe2x80x9cICxe2x80x9d) device under test (xe2x80x9cDUTxe2x80x9d). The inversion handler includes a stationary finger, a movable finger, a shaft, and a driving device. The movable finger is adapted to be moved to releasably secure the IC DUT between the stationary finger and the movable finger. The driving device is coupled to the shaft and is for rotating the shaft approximately one-hundred eighty degrees. Such rotation will rotate the stationary finger and the movable finger in a vertical plane, such that the stationary finger and the movable finger are inverted.